Comments: A zinc enzyme, activated by Co2+. Inhibited by 1,10-phenanthroline and other chelating agents. pH optimum 5.6. Located in storage granules of secretory cells, and active in processing of protein hormones and bioactive peptides. In peptidase family M14 (carboxypeptidase A family). Formerly EC 3.4.17.10, carboxypeptidase H